Engine



Jan. 17, 1967 L. D. WATKINS 3,298,336

ENGINE Filed Oct. 12, 1964 2 Sheets-Sheet 1 INVENTOR Ada/us 0. Warm/v5 MJMLMJA Jan. 17, 1967 L. D. WATKINS I 3,

ENGINE Filed Oct. 12, 1964 2 Sheets-Sheet 2' 1759, 5 5 5 mnfinuu i,

mi? lily/11111114 llllllllllll' I Mum INVENTOR.

L 1/6/05 0. W/PTK/Mf I m, MAL MJM United States Patent Ofifice 3,298,336 Patented Jan. 17, 1967 3,298,336 ENGINE Lucius D. Watkins, Hartland, Wis., assignor to Outboard Marine Corporation, Waukegan, 111., a corporation of Delaware Filed Oct. 12, 1964, Ser. No. 402,997 20 Claims. (Cl. 123148) The invention relates generally to ignition systems for internal combustion engines and more particularly to magneto ignition systems in which the time of spark propagation is varied in accordance with engine starting and engine running conditions.

In one prior magneto ignition arrangement employing an E shaped armature having an ignition coil on the center leg thereof, and a single magnet movable relative to the armature, the time of actuation of a single circuit breaker was shifted to provide starting and running sparks in accordance with engine speed so as to operate selectively at either of two occurrences of maximum current flow through the primary winding of the ignition coil. In such arrangements, every pass of the magnet relative to the E shaped armature produces two current pulses. The first pulse occurs as the magnet travels past the first and second legs of the armature, while the second pulse occurs when the magnet moves past the second and third legs of the armature. The pulses generally occur when the magnet is in maximum registration with the opposed pair of legs.

In this prior arrangement, the circuit breaker was operated to generate a starting spark approximately at the occurrence of the peak current flow in the primary winding resulting from travel of the magnet past the second and third legs of the armature. Circuit breaker operation to provide a running spark was provided at approximately the occurrence of the peak current flow in the primary winding in response to passage of the magnet past the first and second legs of the armature. V

In accordance with the invention, a single E shaped armature and a single magnet movable relative to the armature, are employed with a pair of circuit breakers which will hereinafter be respectively referred to as the running circuit breaker and the starting circuit breaker. The running breaker is arranged for actuation to generate a spark approximately at the occurrence of maximum current flow in the primary winding during travel of the magnet past the first and second armature legs. The starting breaker is arranged for actuation to generate a spark approximately at the occurrence of maximum current flow in primary winding during travel of the magnet past the second and third armature legs.

When the engine is operating at running speeds, actuation of the running circuit breaker produces a spark which ignites the charge in the engine cylinder. Subsequent action of the starting breaker does not result in the initiation of a power stroke either because no spark is generated or because the charge in the cylinder has been previously sparked by the running breaker.

In order to provide an eifective starting spark at a time subsequent to the passage of the magnet past the first and second armature legs, there is provided, in accordance with the invention, means for preventing spark generation by the running circuit breaker as the magnet passes the first and second armature legs. Such means can be either mechanical or electrical. Specifically, mechanical means can be provided for displacing the running breaker from its operating, cam-engaging position when it is desired to avoidthe generation of a spark as the magnet passes the first and second armature legs.

Action of the running breaker to generate a spark .can also be prevented by employing, in the magneto ignition system, electrical means in the form of a switch which serves to render running breaker operation in= effective to generate a spark. Such electrical means can be actuated in various ways, such as for instance, manually, mechanically in accordance with speed or speed control, and electrically.

Other objects and advantages of the invention will become known by reference to the following description and the accompanying drawings in which FIGURE 1 is a partially broken away, schematic view including a wiring diagram, illustrating one embodiment of a magneto ignition system incorporating various of the features of the invention;

FIGURE 2 is a fragmentary view illustrating the cooperative action between a breaker cam and a pair of circuit breakers;

FIGURE 3 is a diagram illustrative of current flow in the primary coil on the armature in response to the passage of the magnet;

FIGURE 4 is a diagrammatic illustration of a modified magneto ignition system in accordance with the invention;

FIGURE 5 is a fragmentary view, partially in section, of the means for operating the switches shown in the embodiments illustrated in FIGURES 1 and 4;

FIGURE 6 is a fragmentary view of a second embodiment of a means for operating the switches shown in the embodiment illustrated in FIGURES 1 and 4;

FIGURE 7 is a fragmentary view of a carburetor including a choke valve arranged to actuate the switches shown in the embodiments illustrated in FIGURES 1 and 4;

FIGURE 8 is a fragmentary view, partially in sec tion, of a mechanical speed responsive means for operating the switches incorporated in the magneto ignition systems shown in FIGURES 1 and 4;

FIGURE 9 is a fragmentary wiring diagram of another embodiment of a magneto ignition system incorporating two circuit breakers;

FIGURE 10 is a fragmentary view illustrative of one mechanical arrangement for rendering impossible operation of a running circuit breaker so as to generate a spark; and

FIGURE 11 is a fragmentary view, partially in section, of a mechanical speed responsive device for rendering a running circuit breaker incapable of generating a spark during starting conditions.

Shown in FIGURE 1 is a magneto ignition system 11 including a flywheel 13 which is fabricated of nonmagnetic material and which is mounted on a crankshaft 15 of an internal combustion engine, or on some other rotatable shaft driven by the crankshaft. Carried by the flywheel 13 is a single magnet 17 having its polar axis extending along a cord perpendicular to a radial line extending from the crankshaft 15. Located at the respective ends or poles of the magnet 17 are polar shoes 19 and 21 of magnetic material, i.e., material which readily conducts magnetic lines of flux. The shoes 19 and 21 include respective pole faces 23 and 25 which extend along the arcuate periphery of the flywheel 13.

The magneto ignition system 11 shown in FIGURE 1 also includes an E shaped armature 27 which is of magnetic material and which has a pair of side or outer legs 29 and 31 and a center leg 33. The armature 27 is fixedly mounted with respect to the crankshaft 15 by any suitable means such that the legs 27, 31 and 33 terminate adjacent to the periphery of the flywheel 13. Accordwinding 39.

generally maximum registration with the armature legs 31 and 33.

The armature legs 29, 31 and 33 are arcuately spaced from each other at angular distances such that the time of the occurrence of peaks A and B is spaced in like manner (see angular distances 0 in FIGURE 3) with respect to crankshaft rotation as the spacing of the times of operation of the running and starting circuit breakers (see 6 in' FIGURE 2). In general, this interval is the same amount by which the spark is advanced and retarded between starting and running conditions.

In accordance with general practice, the secondary winding 39 is connected, at one end, to a spark plug 41 and, at its other end, to a lead 43 connected to a ground 45. The primary winding 37 is also connected at one end, to the lead 43. In accordance with the invention, at its other end, the primary winding is connected through lead 47 to a first or starting circuit breaker 49 including a pair of points 51, 53.

Connected in series with the set of breaker points 51, 53, through lead 54, is a second or running breaker 55 including a pair of points 57, 59. In turn, the running circuit breaker 55 is connected by a lead 61 to the ground 45. Connected between the leads 47 and 61 is a capacitor or condenser 63.

Also in accordance with the invention, there is provided means for rendering operation, i.e., opening, of the running circuit breaker 55 ineffective to produce a spark. In the embodiment shown in FIGURE 1, such means is in the form of a switch 65 connected by leads 67 and 69 in parallel relation with the running breaker 55.

Each of the circuit breakers 49 and 55 is generally of conventional construction. As shown in FIGURE 2, the circuit breakers 49 and 55 respectively include levers or arms 73 and 75 which are supported for pivotal movement intermediate their ends by respective pivot studs or posts 77 and 79. The arms 73 and 75 respectively carry, at one end, the points 51 and 57 which are respectively movable relative to fixed points 53 and 59. At their other ends, the arms include respective followers 81 and 83 engaged with an operating cam 87 supported on the crankshaft 15 or other shaft driven in timed relation to engine operation. Suitable means not shown are provided for electrically insulating the arms 73 and 75 from the cam 87. As is conventional, means in the form of springs 89 and 91 are provided for urging the arms 73 and 75 into position engaging or closing the points 51 and 53, and 57 and 59.

Each of the circuit breakers can be mounted for operation by a different cam. Alternatively, each circuit breaker can be operated by a common cam, such as the cam 85 which is shown in FIGURE 2, and which has a single recessed or relieved portion 93. The recessed or relieved portion 93 is designed and the breakers 49 and 55 are so mounted that, in response to counter-clockwise cam movement, as shown in FIGURE 2, the running circuit breaker 55 is permitted to close, incident to travel of the follower 83 onto the relieved portion 93, in ad- Vance of the occurrence of current flow peak A and is opened, incident to running off of the follower 83 from the 'relieved portion 93, at about the occurence of the current flow peak A. At this point, the starting breaker follower 81 has already entered onto the relieved cam portion 93 so as to close the points 51 and 53.

Under running or high speed conditions, the switch 65 is open. Accordingly, opening of the points 57 and 59 of the running breaker 55, when the starting breaker 49 is closed and the switch 65 is open, interrupts current flow in the primary winding 37, thereby causing generation of a spark at the plug 41.

Under starting or low speed conditions, the switch 65 is closed. Accordingly, closing and subsequent opening of the running breaker 55, as explained immediately above, does not cause spark generation because continued current flow is accommodated through the switch 65. However, when the starting breaker 49 is opened, in response to continued cam rotation and at about the time of the occurence of the second peak current flow B, such opening causes the generation of a spark at the plug 41 at a time when the piston is only slightly in advance of, or approximately at top dead center.

In FIGURE 4, there is shown an alternate magneto ignition circuit 111 including a pair of circuit breakers 149 and arranged in parallel relation to each other. Specifically, the primary winding 137 is connected by leads 147 to the running circuit breaker 155. In turn, the running circuit breaker 155 is connected by lead 161 to ground 145. Connected in parallel with the running breaker 155 and to each of the leads 147 and 161 are a series connected switch and starting breaker 149. The switch 155 constitutes a means for rendering opening of the running breaker 155 inoperative to generate a spark at the plug. A condenser 163 is connected between the leads 147 and 161.

Under starting conditions, the switch 165 is closed. Accordingly, when the circuit breakers 149 and 155 and associated cam are constructed and mounted as are the breakers 49 and 55 and cam 87, shown in FIGURE 2, the starting breaker 149 is closed when the running breaker 155 is opened upon travel of the follower thereof off the relieved cam portion. There is thus available, notwithstanding the open condition of the running breaker 155, a closed circuit extending from the primary winding 137 through the switch 165 and starting breaker 149. Opening of the running breaker 155 is therefore ineffective to generate a spark. However, with the running breaker 155 previously opened, subsequent opening of the starting breaker 149 is effective to generate a spark at the plug.

Under running conditions, the switch 165 is open. Opening of the running breaker 155 by the associated cam is therefore effective to interrupt connection of the primary winding 137 through the leads 147 and 161 and to the ground 145, notwithstanding the closed condition of the starting breaker 149. A spark is therefore generated at the plug upon opening of the running breaker 155. Subsequent opening of the starting breaker 149 is ineffective because of the open condition of the switch 165.

In one preferred construction, as shown in FIGURE 4, the switch 165 comprises a normally open switch which includes an actuator 166 and which is operatively coupled to an engine starting mechanism 168 to afford switch closure during operation of the engine starting mechanism.

The engine starting mechanism 168 is schematically shown and conventionally includes a starter housing 170 containing a recoil or rewinding mechanism 172 to which there is anchored a starting rope or cord 174 having a handle 176 at the outer end thereof. Withdrawal from the housing 170 and release into the housing 170 of the starting cord 174 conventionally affords engine starting. In the specifically disclosed construction, the engine starting mechanism 168 is operatively coupled to the ignition circuit 111 by a lever 178 which, intermediate its ends, is suitably pivotally mounted at 180 on the engine frame or block or on the housing 170, and which includes an arm 182 adapted to operate the actuator 166 so as to close the switch 165 in response to lever movement in the clockwise direction as seen in FIGURE 4.

.which the starter cord 174 passes.

Means are provided for biasing the lever 178 for movement in the clockwise direction in the form of a spring 184 acting between the starter housing 170 and the other arm 1 86 of the lever 178. The other lever arm 186' includes, adjacent its outer end, an aperture 188 through Means are provided on the starter cord 174 for displacement of the lever 178 from its position closing the switch 165 in response to full return of the starting cord 174 into the starter housing 170. In the disclosed construction, such means is in the form of a handle extension 190 which engages the lever arm 186 to rock the lever 178 in the countcrclockwise direction against the action of the spring 184 in response to full retraction of the starting cord 174 into the starter housing 170.

Thus, in operation, withdrawal of the starting cord 174 from the housing 170 to effect engine starting also affords movement of the lever 178 in the clockwise direction under the influence of the spring 184 to close the switch 165 and therefore provide for a starting spark. Upon return of the starting cord 174 into the starter housing 170, the lever 178 is displaced by the handle extension 190 in the counterclockwise direction to afford switch opening and the production of a running spark.

In each of the embodiments shown in FIGURES 1 and 4, both the running and starting breakers are closed in advance of peak A. The running breaker is then opened at the occurrence of peak A and the starting breaker is subsequently opened at the occurrence of peak B. In both embodiments, a switch is employed to prevent spark generation by the running breaker under starting conditions. In the first embodiment, when the running and starting breakers are connected in series, closing of the switch 65 operates to shunt the running breaker 55, thereby rendering breaker operation ineffective. In the second embodiment, when the breakers are arranged in parallel, closing of the switch 165 shunts out the running breaker 155 by permitting current flow through the starting break- Various arrangements can be employed to operate the switches 65 and 165. For instance, the switches 65 and 165 could be directly manually controlled by the operator, i.e., the switches 65 and 165 could be manually operated to afford starting operation. After the engine is started, the switches 65 and 165 could then again be operated to provide a running spark.

Alternatively, the switches 65 and 165 can be operated by a throttle control linkage. Specifically, there is shown in FIGURE 5 a rotatable shaft or member 201 forming a part of a throttle linkage such as shown in Patent No. 2,906,251. As shown, the rotatable member 201 includes a cam part 203 which has common movement with the shaft 201. Located adjacent the shaft 201 is a housing 205 including a switch 265 which is shown in dotted outline. Protruding from the housing 205 is a switch actuator or button 207 located for actuation by the cam 203. If the switch 265 is employed in circuit 11, i.e., in place of switch 65, the switch is normally open. Thus, when the throttle linkage is set at start or slow speed, as shown in FIGURE 5, the switch 265 is opened. However, rotation of the shaft in the clockwise direction to provide increasing speed, also serves to close the switch 265 by operation of the cam 203 against the actuator 205 and to afford generation of a running spark upon opening of the running breaker. If the switch 265 is employed in the circuit 111, the switch 265 is then normally closed and is opened upon shaft rotation to afford increased speed.

In FIGURE 6, there is shown a switch 365 which is shown in dotted outline and which can be either normally opened if employed in place of switch 65 in circuit 11 or normally closed it used in place of switch 165 in circuit 111. The switch 365 is operated by a member or part 301 of a throttle linkage having linear movement. Specifically, the member 301 includes a cam 303. Mounted adjacent the cam 303 is a housing 305 enclosing the switch 365 and supporting a switch button or actuator 307 which is engageable by cam 303. By moving the member 301 to the left as shown in FIGURE 6, so as to increase the speed setting from start or slow, the actuator 307 is depressed by the cam 303 to operate the switch 365 so as to provide a running spark.

In FIGURE 7, there is shown a carburetor 401 including a choke valve 402 and choke shaft 403. In this embodiment, switch 465 corresponds to switches 65 and 165, is shown in dotted outline, is enclosed in a housing 404, and is ope-rated by a cam 405 on the choke shaft 403. The switch can be either normally opened or closed depending upon use in circuit 11 or 111. When the choke valve 402 is closed, as upon starting, the switch 465 affords the generation of a starting spark by preventing effective operation of the running breaker. Upon opening of the choke valve 402, incident to operation at increased speeds, the cam 405 operates the switch 465 to provide a running spark.

Actuation of the switches 65 and can also be automatically controlled in accordance with engine speed. For instance, a vacuum operated switch connected to the throat of a carburetor could be used. In such an arrangement, the switch would be operated in response to development of a predetermined vacuum condition in the carburetor throat. Alternatively, in an outboard motor having a Water pump, a pressure switch responsive to water pressure could be operated in response to the development of a predetermined presssure in the cooling system.

A speed responsive eddy current device can also be employed to operate the switches 65 and 165 after engine starting. In addition, an electrical filter associated with the ignition circuit and responsive to the frequency generated thereby could be used to operate the switches 65 and 165. Such an electrical filter is disclosed in copending application Serial No. 239,162, filed November 21, 1962, now Patent No. 3,220,396. The relay 39 disclosed in said application could be employed to operate either of switches 65 or 165 providing that the frequency sensitive position 35 disclosed in said patent were suitably designed to operate at a desirable speed level intermediate high and low speed operation. In connection with a two-cycle engine, the switches 65 and 165 could be operated in response to crankcase pressure.

In addition to all of the foregoing, a centrifugal governor 501, such as shown in FIGURE 8, can also be used to operate the switches 65 and 165, i.e., to close the switch 65 or to open the switch 165 when sufficient speed is attained. Specifically, in FIGURE 8, there is shown a flange-shaped, rotary cover member 503 which is carried by a crankshaft 515 or other shaft driven by the crankshaft. Mounted on the rotary member 503 is a housing 507 containing a switch 565 which is shown in dotted outline and which can be normally closed it using the circuit 111 or normally opened if using the circuit 11. Extending from the housing 507 is a switch actuator or button 511.

Carried on a guide extending diametrically of the crankshaft 515 from the switch 565 are an opposed pair of weights 513 and 517 which are normally retained adjacent to the crankshaft 515 by a garter spring 519, whereupon the switch 565 remains normally open or closed as the case may be, thereby preventing spark generation by operation of the running breaker. However, upon operation of the engine at sufiicient speed, the weights 513 and 517 are displaced radially outwardly, with consequent engagement of the weight 517 with the actuator 511 to operate the switch 565, thereby providing for a running spark. A slip ring and commutator arrangement are provided for connecting the switch 565 to the other electrical components of the ignition circuits which are shown in FIGURES 1 and 4. Specifically, a commutator 521 is carried on a bracket 523 mounted on a non-rotatable member 525 which may also carry the circuit breakers.

In each of the above embodiments, an electrical switch has been used to render the operation of the running circuit breaker ineffective to generate a spark when starting the associated engine. In the following embodiments, arrangements are disclosed whereby physical operation of the running breaker is prevented to render impossible spark generating activity of the running breaker.

In each of the following embodiments, a magneto ignition circuit 611, such as shown in FIGURE 9, can be employed. Circuit 611 does not include the previously mentioned switch but relies upon mechanical means to render impossible spark generating operation of the running breaker 655 during starting or low speed operation. Specifically, the circuit 611 includes a primary winding 637 which is connected through a lead 641 to a running breaker 655 and a starting breaker 649 which are connected in parallel to each other. Connected in parallel with the breakers 649 and 655 is a condenser 663. The breakers 649 and 655 and operating cam or cams, as the case may be, are arranged so that the running breaker 655 closes and subsequently opens before closing an opening of the starting breaker 649.

One arrangement for rendering the running breaker 655 inoperative to generate a spark is shown in FIGURE 10. Such operation is provided by an car 601 which is engageable with one end of the arm 675 of the running breaker 655 to rotate the arm 675 clockwise as shown in FIGURE 10, against the action of the spring 691, thereby removing the follower 66?: from the cam 687 so as to prevent opening and closing operation of the running circuit breaker 655. Such movement of the arm 675 also serves to electrically open the circuit through the running circuit breaker 655 and to retain this circuit open.

The ear 601 is mounted on a shaft 605 which is journalled by means not shown and which is .ro-ckable by a lever 607 which can be controlled manually by a throttle linkage, or automatically as generally explained with respect to the switches 65 and 165.

In another arrangement, as shown in FIGURE 11, a running breaker 755 such as the breaker 655, is mounted on a block or member 711 which is movable along a track 713 extending radially from an operating cam 787. In this embodiment, the block 711 is located under starting or slow speed conditions so that the follower 715 of the running circuit breaker 755 is clear of the cam 787 and is therefore not operated in response to cam rotation. However, upon an increase in rotative speed, the block 711 moves radially inwardly to operatively engage the follower 783 with the associated cam 787 so as to provide for a running spark. Subsequent closing and opening of the starting circuit breaker is ineffective as the explosive charge has already been ignited by the running spark. In FIGURE 11, the crankshaft disk or member 751 provides a diametrically extending guideway 753 carrying a pair of weights 755 and 757 disposed on opposite sides of the crankshaft 715. The weights 755 and 757 are normally urged toward the crankshaft 715 by a pair of springs 759 and 761 anchored to depending flanges 763 and 765 at the ends of the member 751. Carried on the crankshaft 715 between the cam 787 and member 751 is an axially shiftable collar or dog 767 which is biased toward the disk or member 751 by a spring 769. The collar 767 and weights 755 and 757 cooperate with each other to afford movement of the collar 767 toward the member 751 in response to relatively outward movement of the weights 755 and 761 under influence of increasing speed.

Movement of the collar 767 axially of the crankshaft 715 is translated into motion of the breaker 755 along the track 713 by means of a bellcrank lever 771 which is pivotally mounted on a bracket 773 fixed to the fixed member 711. The bellcrank lever includes a forked arm 775 having its ends engaged in an annular groove 777 in the collar 767. The other arm 779 of the bellcrank lever 771 terminates in a socket fixedly mounted with respect to the running breaker 7 55. Accordingly, upward movement of the collar 767 upon an increase in crankshaft speed serves to rock the bellcrank lever in the clockwise direction and thereby locates the running breaker 755 for engagement by the cam 787. Upon a decrease in speed, the springs 759 and 761 urge the weights 755 and 757 inwardly toward the crankshaft, thereby displacing the collar 767 axially of the shaft 715 away from the disk 751. Such movement of the collar 767 rocks the bellcrank lever 775 in the counterclockwise direction as shown in FIGURE 11 to withdraw the running breaker 755 from a position in operative engagement with the I cam 787.

Various of the features of the invention are set forth in the following claims.

What is claimed is:

1. A magneto system comprising means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, a first and second circuit breaker electrically coupled to said primary winding, means for operating said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, means for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and means for selectively rendering one of said circuit breaker operating means ineffective to produce a spark at said plug.

2. A magneto system comprising means for producing a first peak condition and a second subsequent peak condition of current flow in a primary winding during each full cycle of relative rotation between a magnet and an armature, said means including an armature, a magnet, and an ignition c-oil mounted on said armature and including a primary winding and a secondary winding, a spark plug electrically coupled to said secondary winding, a circuit capable of generating a spark including said primary winding, a first pair of breaker points electrically coupled to said primary winding, and a second pair of breaker points electrically coupled to said primary winding, means for operating said first pair of breaker points approximately at the time of the occurrence of said first peak condition of current flow in said primary coil to produce a spark at said plug, means for operating said second pair of breaker points at approximately the time of the occurrence of said second peak condition of current flow in said primary coil to produce a spark at said plug, and means for rendering one of said breaker point operating means ineffective to produce a spark at said plug.

3. A magneto system comprising means comprising relative rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means for operating said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and switch means electrically coupled to one of said circuit breakers to render operation of one of said circuit breakers ineffective to produce a spark at said plug.

4. The combination in an internal combustion engine of a magneto system comprising means comprising relative rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means for operating said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and switch means electrically coupled to one of said circuit breakers to render operation of one of said circuit breakers ineffective to produce a spark at said plug, and means for controlling the speed of said engine and for actuating said switch means in accordance with engine speed.

5. A combination in accordance with claim 4 wherein said engine speed controlling and switch actuating means comprises a rotatable member.

6. The combination in an internal combustion engine of a magneto system comprising means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature par-ts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means for operating said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and switch means electrically coupled to one of said circuit breakers to render operation of one of said circuit breakers ineffective to produce a spark at said plug, and means responsive to engine speed for actuating said switch means.

7. A combination in accordance with claim 6 wherein said means responsive to engine speed for actuating said switch means is electrically operable.

8. A combination in accordance with claim 6 wherein said means responsive to engine speed for actuating said switch means is mechanically operable.

9. The combination in an internal combustion engine of a magneto system comprising means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means for operating said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and switch means electrically coupled to one of said circuit breakers to render operation of one of said circuit breakers inefiective to produce a spark at said plug, and manual means for operating said switch means.

10. A magneto system comprising means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of rela- 1 0 tive rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, a spark generating circuit including said primary winding, a first and second pair of breaker points electrically coupled in series to said primary winding, and a switch connected in parallel with one of said pairs of breaker points, and means for operating said first and second pairs of points at times approximately corresponding to the occurrence of said peak conditions of current flow in said primary winding, and means for operating said switch in accordance with engine speed.

11. A magneto system comprising means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing a first peak condition and a second subsequent peak condition of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, a spark generating circuit including said primary winding, a first and second pair of breaker points electrically coupled in series to said primary winding, and a switch connected in parallel with said first pair of breaker points, and means for operating said first pair of points at times approximately corresponding to the occurrence of said first peak condition of current flow in said primary winding, means for operating said second pair of points at times approximately corresponding to the occurrence of said second peak condition of current flow in said primary winding, and means for closing said switch during engine operation below a predetermined speed and opening said switch during engine operation above said predetermined speed.

12. A magneto system comprising means for producing two peak conditions of current flow in a primary winding during each full cycle of relative rotation between a magnet and an armature, said means including an armature, a magnet, and an ignition coil mounted on said armature and including a primary winding and a secondary winding, a spark plug electrically coupled to said secondary winding, a spark generating circuit including said primary winding, a first circuit segment electrically coupled to said primary winding and including a first pair of breaker points, a second circuit segment electrically coupled to said primary winding in parallel with said first circuit segment and including a second pair of breaker points, and a switch connected in series with said second pair of breaker points, means for operating said first and second pairs of points at times approximately corresponding to the occurrence of said peak conditions of current flow in said primary winding, and means for operating said switch in accordance with engine speed.

13. A magneto system comprising means for producing a first .peak condition and a subsequent second peak condition of current flow in a primary winding during each full cycle of relative rotation between a magnet and an armature, said means including an arm ature, a magnet, and an ignition coil mounted on said armature and including a primary winding and a secondary winding, a spark plug electrically coupled to said secondary winding, a .spark generating circuit including said primary winding, a first circuit segment electrically coupled to said primary winding and including a first pair of breaker points, a second circuit segment electrically coupled to said primary winding in parallel with said first circuit segment and including a second pair of breaker points, and a switch connected in series with said second pair of breaker points, and means for operating said first pair of points at times approximately corresponding to the occurrence of said second peak condition of current flow in said primary winding, means for operating said second pair of points at times approximately corresponding to the occurrence of said first peak condition of current flow in said primary winding, and means for opening said switch during engine operation below a predetermined speed and for closing said switch during engine operation above said predetermined speed.

14. A magneto system comprising means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means including rotary shaft means and cam means fixedly carried on said shaft means for operating said first circuit breaker during the occurrences of one of said peak conditions of current flow to produce a spark at said plug and for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and means for rendering operation of said second circuit breaker ineffective to produce a spark at said plug.

15. A magneto system cmprising means for producing a first peak condition and a second subsequent peak condition of current flow in a primary winding during each full cycle of relative rotation between a magnet and an armature said means including an armature, a magnet, and an ignition coil mounted on said armature and including a primary winding and a secondary winding, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means including rotary cam means for operating said first circuit breaker approximately during the occurrence of said first peak condition of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of said second peak condition of current fiow to produce a spark at said plug, means mounting said first circuit breaker for movement relative to a position in operative relation to said rotary cam means, and means for displacing said first breaker from said position to render said means for operating said first circuit breaker ineffective to produce a spark at said plug.

16. A magneto system comprising means for producing two peak conditions of current flow in a primary winding during each full cycle of relative rotation between a magnet and an armature, said means including an armature, a magnet, and an ignition coil mounted on said armature and including a primary winding and a secondary winding, a spark plug electrically coupled to said secondary winding, rotary cam means having a breaker operating segment, first and second circuit breakers electrically coupled to said primary winding and mounted in relation to said cam means to afford operation of said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, and for operation of said second circuit breaker during the occurrence of the other of said peak conditions of current flow, said circuit breakers each including a pivotally mounted lever having a follower engageable by said cam, means biasing ,s-aid lever for engagement of said follower with said cam, a first contact carried by said lever, a second contact fixedly mounted for engagement by said first contact solely during engagement of said follower with said cam segment, and means engageable with said lever of one of said circuit breakers for preventing engagement of said follower thereof and said cam segment to thereby retain said contacts thereof open.

17. An ignition device in accordance with claim 16 including manually operable means for operating said "means engageable with said lever.

18. A magneto system comprising means for producing a first peak condition and a second subsequent peak condition of current flow in a primary winding during each full cycle of relative rotation between a magnet and an armature, said means including an armature, a magnet, and an ignition coil mounted on said armature and including a primary winding and a secondary winding, a spark plug electric-ally coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means including rotary cam means for operating said first circuit breaker approximately during the occurrence of said first peak condition of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of said second peak condition of current flow to produce a spark at said plug, means mounting said first circuit breaker for movement relative to a position in operative relation to said rotary cam means, and speed responsive means for displacing said first breaker from said position to render said means for operating said first circuit breaker ineffective to produce a spark at said plug.

19. The combination in an internal combustion engine of a starting mechanism including a starter rope, and a recoil mechanism connected to said starter rope, a magneto system including means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing two peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding,

-means for operating said first circuit breaker during the occurrence of one of said peak conditions of current flow to produce a spark at said plug, and for operating said second circuit breaker during the occurrence of the other of said peak conditions of current flow to produce a spark at said plug, and switch means electrically coupled to one of said circuit breakers to render operation of one of said circuit breakers ineffective to produce a spark at said plug, and switch means electrically coupled to one of said circuit breakers to render operation of one of said circuit rbeakers ineffective to produce a spark at said plug, and means operatively connecting said starting mechanism and said switch means for operation of said switch means to render operation of said one circuit breaker ineffective to produce a spark at said plug.

20. The combination in an internal combustion engine of a starting mechanism including a recoil mechanism and a starter rope connected to said recoil mechanism for withdrawal therefrom and for rewinding thereon, a magneto system including means comprising relatively rotatably mounted armature and magnet parts and an ignition coil wound on said armature part and including a primary winding and a secondary winding for producing successive first and second peak conditions of current flow in said primary winding during each full cycle of relative rotation between said magnet and armature parts, a spark plug electrically coupled to said secondary winding, first and second circuit breakers electrically coupled to said primary winding, means for operating said first circuit breaker during the occurrence of said first peak condition of current flow for the production of a spark at said plug and .for operating said second circuit breaker during the occurrence of said second peak condition of current flow for the production of a spark at said plug, and normally open switch means electrically coupled, in series, with said second circuit breaker, a lever, means mounting said lever to afford 13 14 movement relative to a position closing said switch, References Cited by the Examiner means :biasing said lever toward said position, and means UNITED STATES PATENTS connecting said starter rope and said lever for affording 1 128 219 2/1915 Bordeaux 123 185 movement of said lever to said position in response 1 9/1939 Weston I 123*179 to Withdrawal of said rope from said recoil mechanism 5 2:982:805 5/1961 Glenda}, et i 123 149 and for effecting movement of said lever from said position in response to rewinding of said rope by said MARK NEWMAN, Primary Examiner.

recoil mechanism LAURENCE M. GOODRIDGE, Examiner. 

1. A MAGNETO SYSTEM COMPRISING MEANS COMPRISING RELATIVELY ROTATABLY MOUNTED ARMATURE PART AND AND AN IGNITION COIL WOUND ON SAID ARMATURE PART AND INCLUDING A PRIMARY WINDING AND A SECONDARY WINDING FOR PRODUCING TWO PEAK CONDITIONS OF CURRENT FLOW IN SAID PRIMARY WINDING DURING EACH FULL CYCLE OF RELATIVE ROTATION BETWEEN SAID MAGNET AND ARMATURE PARTS, A SPARK PLUG ELECTRICALLY COUPLED TO SAID SECONDARY WINDING, A FIRST AND SECOND CIRCUIT BREAKER ELECTRICALLY COUPLED TO SAID PRIMARY WINDING, MEANS FOR OPERATING SAID FIRST CIRCUIT BREAKER DURING THE OCCURRENCE OF ONE OF SAID PEAK CONDITIONS OF CURRENT FLOW TO PRODUCE A SPARK AT SAID PLUG, MEANS FOR OPERATING SAID SECOND CIRCUIT BREAKER DURING THE OCCURRENCE OF THE OTHER OF SAID PEAK CONDITIONS OF CURRENT FLOW TO PRODUCE A SPARK AT SAID PLUG, AND MEANS FOR SELECTIVELY RENDERING ONE OF SAID CIRCUIT BREAKER OPERATING MEANS INEFFECTIVE TO PRODUCE A SPARK AT SAID PLUG. 